This is needed in order to support use cases where we have several account.move.line on an account_id of internal_type 'bank' inside a single account.move. Indeed, each journal item should be linked to a bank statement line in order to disappear from the bank reconciliation widget and, previously, setting the reference to the second bank statement line was removing the first as both info had to be filled in a single m2o. OPW: 696842